Centrifugal drier.



K. & A. WARD.

CENTRIFUGAL DRIER. APPLICATWN men Araiao. 1914.

Patented Jan. 30, 1917.

3 SHEETSSHEET 2- K. & A. WARD.

CENTRIFUGAL DRIER.

APPLICATION HLED APR-30, m4.

Patented Jan. 30, 1917.

3 SHEETS-SHEET 3- other by blades or vanes'85.

KARL WARD AND ALBERT WARD, OF STOCKHOLM, SWEDEN.

CENTRIFUGAL DRIER.

Specification of Letters Patent.

Fatented Jan. 30, 1917.

Application filed April 30, 1914. Serial No. 835,392.

To all whom it may concern:

Be it known that we, KARL WARD and ALBERT lVlinD, subjects of the King of Sweden, residing at Odengatan 39, Stockholm, Sweden, have invented new and useful Improvements in Centrifugal Driers, of which the followingis a specification.

The present invention has for its object to provide an apparatus for continuously separating, by the aid of centrifugal force, liquid from liquid-holding, more or less finely granular material, as for instance finely crushed minerals and rocks, peat, cellulose and other fibrous materials, precipitated and crystallized masses in chemical, technical and other factories, sediments from liquid purifying works, etc. Thus a centrifugal apparatus for more or less complete drying of various liquid-holding material is provided, or, shortly, a centrifugal drier.

In the drawing, Figure 1 shows a vertical longitudinal section of such an apparatus, taken through its axis; Fig. 2, upper part, a vertical cross section on the line AB in Fig. l; and lower part, a cross section on the line C-D in Fig. 1; Fig. 3 a vertical cross section on the line EF in Fig. 1; Fig. l part of the aforesaid section on UD on a larger scale; Fig. 5 part of Fig. l on a larger scale; Fig. 6 a diagrammatical end view; Figs. 7 and 9 diagrammatical sections on the line G-H; and Figs. 8 and 10 correspending sections on the line IK in Fig. 1.

The main parts of the present centrifugal drier are a drum rotating around an aXis and one or more endless bands running over rollers in the said drum, the moist mass destined to be dried being introduced upon the inner side or portion of said bands. Further, the invention comprises the following features: Thedrum 20 rotating around a shaft 1% comprises a peripheral wall 42 and two end walls 45 and 40. Therein is arranged one, or preferably several introduction and separation chambers 2; one or preferably several inlet channels 1 running in one end wall 45 of the drum from near the shaft l-l outward so as to open into the rear end of each of said chambers 2. These channels are formed between the inner portion and the outer one 67 of the end wall 45 of the drum and are separated from each The outer wall 67 is provided with an opening 86 surrounding the shaft and serving to receive the mass to be dried which is supplied through a stationary pipe 66. The shaft let rests in two bearings 71 carried by pedestals 87 on a bottom frame 88, or in other suitable manner. The driving power required for rotating the drum is supplied for instance by a belt pulley with belt, as shown, or by a motor connected directly to the shaft 14-, or in other suitable manner. Further there isarranged in'the drum 20 one, or preferably several, substantially longitudinally extending endless bands 3, each of which is fed forward either intermittently, or preferably continuously, over two end rollers 6, 17, supported by the end walls 45 and 40 respectively of the drum. The bands 3 are so arranged, that the first portion of the inner side of each band 3, viz. that portion thereof which extends from the end roller 6 to a supporting roller 7 carried by a central wheel or spider 68, forms a movable outer wall of each of the liquid separation chambers 2, while the remaining portion of the inner side of each band continues to each of the end rollers 17 which are supported by carriers 39 held to the end wall 40, for instance by means of clamps and screws 90, preferably so as to be rotatable. The supporting rollers 7 in some cases may be dispensed with, but make the construction safer. The bands pass over the rollers 17 and in an outward direction with relation to the shaft 14, and then they return to the end rollers 6. The rollers 6 and 7 are so positioned, that the inner side of each band, running between them is laterally perpendicular, or nearly so, to a radius of the shaft 14 passing through the center line of the band thus so as to form an angle 0: with said perpendicular which is equal to or near zero,

(see Figs. 7 and 8). On the contrary, each of the end rollers 17 can be so adjusted by means of its rotatable carrier 39, that the angle 6 (see Fig. 3) between its longitudinal direction and a line perpendicular can be greater the friction coefficient is between the band 3 and theiparticlesiof the mass pressed against it by the centrifugal force, the said angle a is increased during the passage of the band from the supporting roller 7 to the end'roller 17 (see Fig. 3) from zero or near zero at the roller 7 to the value 5 at the roller 17. Herein lies one of the greatest advantages of the present invention, viz. in that initially, when the mass resting thereon has a large percentage of moisture and thus a smaller friction against the band, the latter also has a rather small lateral inclination oabut that the said inclination is increased, as the band proceeds toward the roller 17 and the coeliicient of friction of the mass against the band increasesas its moisture decreases. is obvious, that the drying capacity of the apparatus can be highly increased by giving the lateral inclination (5 of the roller 17, (Fig, 3) the highest value which is possible without causing the solid particles to slide off the band laterally over its. edge 41 (Figs. 7 and 8).

F or conducting off the liquid pressed from the massduring its passage from the supporting rollers 7 to the end rollers 17 there are openings or tubular pieces as in the pe ripheral wall 42 of the drum, leading out into the free atmosphere. Around these is a stationary annular channel 14:, a discharge pipe 8 3 leading from the lowest point thereof. v, V V I V For conducting ofi'the dried mass which is torn away from the bands 3 in passing overthe end rollers 17 the following arrangement is provided. At the end wall r-O, .there is arranged a peripheral wall 21 surrounding the rollers 17 and having openings 18, each substantially registering with the rollers 17and carrying a discharge tube 19., Externally on the wall 21 there is arran ed an annular channel 22 surroundin :3 b

the same, the openings 18 with their tubes 19 discharging into said channel, which is limited by a pair of end walls 23, one on either side of the openings 18. From the outerportion of each wall 23 a flange 24 projects (Fig. 1). On both of said flanges 2%. a, discharge belt 25 runs so as to embrace about half the periphery of said flanges, said belt running also over the pulleys 28, 29 and 30, Fig. 6, the last-mentioned of which is preferably arranged for instance on a lever 32, movable around a stationary shaft 31 and actuated for instance by a weight 33 so as to tighten the belt automatically. Registering with the portion of the periphery of the flanges 24:, which is not embracedby the belt 25, ispartly adischargehopper 34:, partly a return channel 35 leading down to the portion of the belt running toward the flanges 24:. The bottom wall of thedischarge hopper and the bottom of the return channel at their upper ends considerable, to choose the distance from the shaft l t to the supporting rollers 7 considerably smaller than to the end rollers 6, so that the first portion of the inner side of each band 3, extending from the end roller 6 to "the supporting roller 7 and forming outer wall ofthe introduction and separation chamber 2, will converge toward the axis. In such case also a device is provided in connection with the chamber 2, by which it has been made possible to perform a preliminary separation therein of the mass from the major portion of liquid initially accompanying it sothat only a smaller por tion of saidliquid' will accompany the mass on to the rear portion of the band, extend ing from the supporting roller 7 t0 the end roller 17 and serving to perform the more complete, final drying operation. The said preliminary separating" device is characterized by the following features: In the inner wall 10 of each chamber 2 are provided ports 9 leading to a chamber 11 inside said wall, and further discharge pipes 12 lead from said chamber out into the atmosphere. Around the free outer ends of the pipes 12 there is arranged a stationary, annular channel 13, from the lowest point of which leads a discharge pipe 82. For effecting the said preliminary separation of liquid in a satisfactory manner, it is obviously necessary, that the ports 9 as well as the pipes 12 lie at a greater distance from the axis of the drum than thefleXion point 8 of the band 3 which is situated on the innermost generatriX of the roller 7. For enabling the bands 3 to be tightened, each of the end rollers 6 is arranged in' a carrier 46 which canbe slid at will in a sleeve 79 projecting. from the wall 415, by means of a screw 89 or other suitable device.

, For further increasing the liquid separating action in the separation chamber 2, a set of closely arranged plates 60, so called angle plates, may be placed therein so as to form a suitable angle with the shaft 14 and thus divide the liquid into radially thin ticles from passing directly from the outer ends of the supply channels 1 to the ports 9. For enabhng as many of the plates 60 as possible to be utilized, there is arranged, 13o

in the portion of the chamber 2 which is between the inner edges 63 of the plates 60 and the inner wall 10 of said chamber, a

partition 6 1, extending from the projection 61 of the first plate at least to a point 65, forming an edge (Fig. 5) over which the purified liquid may flow to the ports 9. The said edge 65 obviously, like the ports 9 and the discharge pipes 12, must be situated at a greater distance from the shaft it than the fiexion point 8 of the band 3.

For preventing liquid with solid particles from being ejected by the centrifugal force between the outer edges 15 on the side walls at and rear wall 5 (see Figs. l and 5) on one hand and the band 3 on the other, there are provided packing bands 58, which are secured at their outer portions, for instance by means of screws and clamping ribs 59, to the aforesaid walls 4 and 5, while their inner portions bear against the band 3 under the action of the pressure so as to form a selfpacking device.

The endless bands 3 may be fed forward either intermittently or, preferably, continuously. In Fig. 1, an example is shown of a continuously acting driving device for the bands, by means of which the driving power is derived from a friction disk 17 arranged on the shaft 14 of the apparatus. From said disk, the driving power is transmitted to the end rollers 17 by means of the friction disk 48, shaft 49, bevel gearing 50, shaft 51, cylindrical toothed gearing 52, sprocket wheel 53, chain 54, sprocket wheels 55, shaft 56 and bevel gearings 57. This driving device, by means of which the feeding speed of the bands 3 can be changed, while the apparatus is running, from Zero to a sufficient maximum, can easily be replaced by other known devices.

In each of the rotatable carriers 39 for the end rollers 17 there is also arranged a guide roller 69-. To cause the band portions coming from the rollers 7 and 69 to retain their proper angular relations to the end rollers 17 and 6 so as not to become displaced sidewise regardless of the angular position of the carrier 39 with the rollers 17 and 69 mounted thereon, an arrangement is provided consisting in that the axis of rotation of each carrier RS (Fig. 1) runs through the center of the generatrix on which the band arrives at the roller 17, as well as through the center of the generatrix on which the band leaves the roller 69. If this were not the case, the band would have a tendency to climb upon the side flange of each of the rollers 17 and 6 in most angular positions of the rollers 17 and 6. For the sake of safety, such flanges should preferably be arranged on at least one or two of the four rollers 6, 7, l7 and 69 although they are omitted in Fig. 1 for the sake of simplicity.

For duly tightening the sprocket chain 5% which is necessary after each angular dis placement of the carriers 39, a guide wheel 72 is arranged (Figs. 1 and 3) together with a counterweight 73 on an arm 74 rotatably arranged on the shaft 14, but capable of being secured thereto after rotation by means of a pair of screws 75. If the anglelfi (Fig. 3) is somewhat increased, all the sprocket wheels 55 will be approached to the axis of rotation of the apparatus, and ,then obviously the arm 74 in Fig. 3 must be rotated somewhat in anti-clockwise direction for sufficiently tightening the sprocket chain.

The apparatus operates in the following manner: After the drum 20 together with all its contents has been brought into a suliiciently rapid rotation and the forward movement of the bands 3 has been controlled to a suitable speed by adjusting the frictional disk 17, the moist mass destined to be dried and arriving for instance through a tubular conduit 66 is introduced to the inner ends of the channels 1, passes outward through these and arrives at the rear ends of the chambers 2. Here the solid particles as well as the liquid are pressed outward against the inner side of each band 3 serving as amovable outer wall of the chamber 2. The solid particles being specifically heavier than the accompanying liquid (a condition for the operation of the apparatus), the former, together with liquid adhering thereto and filling the spaces therebetween, deposit themselves as a layer on the band and are tightly pressed against said band by the centrifugal force. The rest of the'liquid is collected inside the said layer, 2'. e. nearer the inner wall 10. As more of the moist mass enters the chambers 2 from the inlet channels 1, the aforesaid layer which is pressed against the band 3 and which contains a comparatively small amount of liquid, accompanies the band forward over the roller 7 and then will be finally dried while passing from the supporting roller 7 to the end roller 17, as will be more fully described hereinafter. The liquid liberated from solid particles which is collected in the chambers 2 inside the layer on the band, leaves the said chambers through the ports 9 and enters the chamber 11, from which it escapes through the pipes 12, and is then ejected from the outer ends of these pipes into the channel 13, from which it is led away through the discharge pipe 82.

After the solid particles, during their passage through the separation chambers as above described, have bene liberated of the major portion of the liquid originally accompanying them, the layer, consisting of said particles together with a comparatively small quantity of liquid and sticking to the band by the centrifugal action, advances under continued removal of liquid toward the obliquely arranged end roller 17, the inner generatrix of which forms the angle 6 (see Fig. 3) with the periphery. On account of the oblique position of the end roller 17 the band 3 is caused, during its passage from the supporting roller 7 to the said end roller, to increase more and more its angle a of lateral inclination (see Figs. 7 and 8), until the band, when it arrives on to the end roller 17, reaches the maximum value 6 of such lateral inclination (see Fig. 3). Thus for instance, in a section GH, situated nearer the roller 7, the lateral angle a is smaller than in a section ll-K, situated farther away from said roller (see Figs. 7 and 8). Figs. 7 and 8 and the corresponding parallelograms of forces shown on a larger scale in Figs. 9 and 10 show clearly how the final drying occurs on the way between the rollers 7 and 17. For instance, in the sections G-H and I-K, it is the lateral components L,N and L N of the centrifugal forces L -M and L M which tear off liquid from the solid particles and force it therefrom laterally toward the edge 41 of the band, where the liquid leaves the band and is-ejected toward the peripheral wall 42 of the drum. The said lateral components evi' dently also tend to move the solid particles to the edge 41 but this is prevented by the friction forces L,P and L "P between the solid particles and the band acting in opposite direction, if the said forces, which in their turn are equal to the product of the normal components L O and 11 -0, and the friction coefficient between the solid particles and the band 3, are greater than L,'N and L N respectively. For in stance, in the cross section Gr-H situated nearer the roller 7 (see 7), in which the mass is only a little more dry than in passing the roller 7, the angle 0: of lateral inclination of the band is also comparatively small, whence also the lateral component I -N of the centrifugal force L 'M (see Fig. 9) is comparatively small. On the contrary, in the cross section IK (see Fig. 8) situated farther away from the roller 7, in which the mass has had time to be more dry than in the aforesaid section, the lateral angle or is greater, whence also the component L N (see Fig. 10) of the centrifugal force L M is larger than in the first named section. This is desirable, because when the mass is more moist, it cannot maintain so great a lateral inclination without the solid particles yielding to the tendency to accompany ftheexpelled' liquid toward the outer edge 41 of the band 3, From the aforesaid it is thus clear, ,that'the lateral components L N,, L N etc., effecting the final drying will be the greater, the more the particles approachthe roller17 at which the forces assume their maximum value.

i This is also desirable, as the liquid remainlng'on the solid particles will adhere thereto with greater force; when its quantity detrifugal force from the bands 3 during their I passage over the end rollers 17, and is ejected through the tubular pieces 19, partly directly into the discharge hopper 34, partly out on the belt 25, and partly into the return channel 35 leading to said belt 25. The particles whichhave not been ejected directly into the discharge hopper 34', will accompany the belt 25 to the generatrix 37 on the belt roller 29, and at the said generatrix thepa'rticles are torn off from the belt and continue out into the discharge hopper 34. The particles discharged from the mouth 38 of said hopper are collected and taken care of in any suitable, already known manner;

The centrifugal drier in question affords many and great advantages. Thus by means of the same, liquid can be expelled from a moist'mass without it being necessary for the liquid to pass through. for instance filtering cloth .or paper, or other porous sheets, etc. By reason hereof the endless bands can be made of some strong and elastic and therefore very durable material, as for instance cold rolled steel, other cold rolled metals or metal alloys indifferent to acids and bases, rubber, leather, etc. Further the apparatus cleans itself continuously, the bands in passing over the end rollers 17 being totally freed from the dried mass by the action of the centrifugal force so as to return in a cleaned state to the chambers 2 where they will receive fresh mass to be dried. Should the mass some time be especially sticky so that the centrifugal force alone will not be sufl'icient for cleaning the bands, a scraper plate 76 may easily be provided which preferably is so secured, in the preferred form to the rotatable holder 39, that the free edge of the plate 76 will bear against the band 3 somewhere at or shortly behind its passage over the end roller 17 (see Fig. 1). Further the apparatus in questlon requires an extremely small amount of attendance. introduced into the apparatus automatically, and also not only theseparated liquid but also the dried material is discharged automatically. As known, filtering presses must be taken apart time after time for enabl ng the solid mass deposited on the filtering cloth to be taken out of the apparatus, which Thus the material to be dried is 7 then again must be assembled. Finally it may be mentioned, that with the present centrifugal drier there is no difficulty in separating even the most finely disintegrated particles from liquid accompanying them. In filtering presses, as known, this is very difficult, because if a very dense filtering cloth is chosen, the great inconvenience will at once arise that the cloth is soon obstructed, so that not even the liquid can penetrate therethrough except with the greatest difficulty. This has the consequence that the capacity is reduced and that the expensive filtering cloth is often split to pieces. If on the contrary amore porous filtering cloth is chosen, the finest particles will accompany the liquid through the cloth so that the filtration will then be incomplete.

Having now particularly described the nature of our invention and the manner of its operation, what we claim is:

1. In a centrifugal drier, the combination with a rotary member, of a conveyer for the material to be dried carried by the said rotary member and mounted for independent movement in a direction substantially longitudinal with respect to the axis of the latter, the conveyer being disposed so that its innermost surfaces increase in inclination with respect to the perpendicular to the line of centrifugal force from one efi'ective end of the conveyer to the other.

2. In a centrifugal drier, the combination with a rotary member, of a conveyer for the material to be dried carried by the said rotary member and mounted for independent movement in a direction substantially longitudinal with respect to the axis of the latter, the conveyer being disposed so that its innermost surfaces increase in inclination with respect to the perpendicular to the line of centrifugal force from one effective end of the conveyer to the other, means for supplying material to be dried to that end of the conveyer having the least inclination, and means for separately collecting the solid and liquid products as they are cast off from the conveyer.

3. In a centrifugal drier, the combination with a rotary member, of a conveyer for the material to be dried carried by the said rotary member and consisting of an endless belt mounted for independent movement in a direction substantially longitudinal with respect to the axis of the said member, the said belt being disposed so that its innermost surfaces increase in lateral inclination with respect to the perpendicular to the line of centrifugal force from one effective end of the conveyer to the other.

4:. In a centrifugal drier, the combination with a rotary member, of a conveyer for the material to be dried carried by the said r0- tary member and mounted for independent movement in a direction substantially longitary member and consisting of an endless belt mounted for independent movement in a direction substantially longitudinal with respect to the axis of the said member, the innermost stretch of the belt being maintained offset so that its fiexion point is situated nearer to the axis of the rotary member than the effective ends of the conveyer,

the belt being disposed so that that portion of its innermost stretch situated in advance of the fiexion point has a definite lateral inclination with respect to the perpendicular to the line of centrifugal force, the other portion of the inner belt stretch being disposed so that its innermost surfaces increase in inclination with respect to the perpendicular to the line of centrifugal force from the fiexion point to the opposite end of the conveyer.

6. In a centrifugal drier, the combination with a rotary member, of a conveyer for the material to be dried carried by the said rotary member and consisting of an endless belt mounted for independent movement in a direction substantially longitudinal with respect to the axis of the said member, the innermost stretch of the belt being maintained so that its fiexion point is situated nearer to the axis of the rotary member than the effective ends of the conveyer, the belt being disposed so that that portion of its innermost stretch situated in advance of the fiexion point has a definite lateral inclination with respect to the perpendicular to the line of centrifugal force, the other portion of the inner belt stretch being disposed so that its innermost surfaces increase in inclination with respect to the perpendicular to the line of centrifugal force from the fiexion point to the opposite end of the conveyer, means for supplying the material to be dried to the inner surfaces of the first mentioned portion of the innermost belt stretch, and means for separately collecting the solid and liquid material. as cast off from the other portion of the said belt stretch.

7 A centrifugal drier comprising a rotatable drum having separation chambers arranged therein and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined at right angles to the drum axis and axis inclined with respect to the axes of the first rollers, the first two rollers being positioned adjacent to the opposite ends of the vsaid chambers, an endless band passing around the said rollers, means for rotating the drum, and means for propelling said band during operation of the drum.

8. A centrifugal drier comprising arotatable drum having separation chambers arranged therein and provided in their outermost walls with discharge openings, two

axially spaced rollers journaled within the drum and having their .axes arranged inclined at right angles to thedrum-axis and disposed nearly in tangential relation to the latter, a third roller. positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respect to the axes of the first rollers, the first two rollers, being positioned adjacent to the opposite ends jof the said chambers, an endlessband passing around the said rollers, means for rotating the drum, and means for propellingsaid band during operation of the drum, the intermediate one of the first named rollers being-disposed inwardly of the'other rollers radially.

9. A centrifugal drier comprising a rotatabledrum having separation chambers arrangedtherein and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined. at right angles to the drum axis and disposed nearlyin tangential relation tothe latter, a third roller positioned in axially spaced relation to the first named rollers and'being journaled upon a transverse axis inclinedwith respect to the axes 'ofthe first rollers, the first tworollers being positioned adjacent to the opposite ends of the said chambers, an'endless band passing around the said rollers, means for rotating the drum and means for propelling said band during operation ofthe drum,-the intermediate one of the first named rollers beingdisposed-inwardly ofathe other. rollers radially, the-said port in f thechamber being arranged outwardly of the innermost part of :the' belt passing over'the intermediate rollerain a radial direction.

110. A. centrifugal drier-comprisingia rotatable drum having separation chambersarranged thereinand provided intheir outermostxwalls-withdischarge openings, two axiallyspaced rollers journalejdwvithin the dr-urnand having their. axes-arranged in clined. at rightangles to. the drnmoaxis and disposed nearlytin tangentialrelation to the latter, a :third roller positioned in-eaxially 1,a13,ess

spaced relation to the first named rollers and being journaled upon a transverse axis inclinedwith respect to the axes of the first rollers, the first two rollers'being positioned adjacent to the opposite ends of the said chambers, an endless band passingaround the said rollers, means for rotating the drum, and means for propelling said band during operation of the drum, the intermediate one of the firstnamed rollers bechamber at a point spaced equi-distant from the axis o'f'the drum with relation to the said discharge port and extending to the atmosphere.

11. A centrifugal drier comprising a rotatable drum having separation chambers arranged. therein and provided in their outermost walls with discharge openings, two axially spaced rollers j'ournaled within the drum and'having their axesarranged inclined "at right angles to the drum axis and disposed nearlyinftangential relation to the latter, a third roller positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respectto the axes of the first rollers, vthe firsttwo rollers beingpositioned adjacent to the opposite ends of the said chambers, an endless band passing around the said rollers, means for rotating the drum, and means for propelling said band during operation of the drum, theintermediat e one of .the first named rollersbein'g disposed-inwardly of the other rollers radially, the said port in;the chamber being arranged outwardly ofthe innermost part of the belt passing over the intermediate roller in. a radial direction, and means for mounting the last:named inclined roller for rotation upon its axisand for angular adjustment'upon an axis disposed parallel to the axis of the drum.

12. A centrifugal drier comprising a rotatable drum having separation chambers arranged therein and provided in their outermost walls, with discharge openings, two axially spaced rollers' journaled within the drum and having their axes arrangedinclined at right: angles to the drum axis and disposednearly in tangential relation to the latter, a third rollerfpositione'd in axially spaced relation :to the first ,named v rollers and being-journaled upon a transverse axis inclined with respect tothe axes of the first rollers, the first two rollers being positioned adjacent to the opposite ends of 'the said chambers, 'an endless band p'assing around the said rollers, means for, rotating the drum, andla carrier journaled within the drum upon a longitudinal axis for mounting the last named inclined roller rotatably.

13. A centrifugal drier comprising a rotatable drum having separation chambers arranged therein and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined at right angles to the drum axis and disposed nearly in tangential relation to the latter, a third roller positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respect to the axes of the first rollers, the first two rollers being positioned adjacentv to the opposite ends of the said chambers, an endless band passing around the said rollers, means for rotating the drum, and means for securing the said carrier in a-ngularly adjusted position.

14. A centrifugal drier comprising a rotatable drum having separation chambers arranged therein and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined at right angles to the drum axis and disposed nearly in tangential relation to the latter, a third roller positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respect to the axes of the first rollers, the first two rollers being positioned adjacent to the opposite ends of the said chambers, an endless band passing around the said rollers, means for rotating the drum, and a guide roller j ournaled upon the said carrier in longitudinally spaced rela tion to the third roller of the series carried thereby upon an axis parallel thereto and for engagement with the outer surface of the said band.

15. A centrifugal drier comprising a rotatable drum having separation chambers arranged therein and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined at right angles to the drum axis Hi disposed nearly in tangential relation to the latter, a third roller positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respect to the axes of the first rollers, the first two rollers being positioned adjacent to the opposite ends of the said chambers, an endless band passing around the said rollers, means for rotating the drum, a longitudinally adjustable holder mounted upon the end of the drum bearing the terminally disposed one of the first named rollers and rotatably mounting the same, and means by which the said holder may be adjusted.

16. A centrifugal drier comprising a rotatable drum having separation chambers arranged therein' and provided in their outermost walls with discharge openings, two axially spaced rollers journaled within the drum and having their axes arranged inclined at right angles to the drum axis and disposed nearly in tangential relation to the latter, a third roller positioned in axially spaced relation to the first named rollers and being journaled upon a transverse axis inclined with respect to the axes of the first rollers, the first two rollers being positioned adjacent to the opposite ends of the said chambers, an endless band passing around the said rollers, means for rotating the drum, the drum being provided in its outer wall with a discharge opening in alinement with the said band at the last named roller, the outer surface of the drum at this point affording a belt surface, a plurality of axially pivoted pulleys mounted in radially.

spaced relation to the said belt surface of the drum and in circumferentially spaced relation to each other, a band passing around the said pulleys and having its outer surface traversing a portion of the said belt surface of the drum, the belt being adapted to be propelled by the drum, and a discharge hopper disposed adjacent to the exposed portion of the said belt surface of the drum and opening in the direction of the said surface. In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses. a

KARL WARP. ALBERT WARD. Witnesses:

BIRGER Nonnrnnn'r, H., TELANDER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

, Washington, D. C. 

